肩锁关节脱位改良型Dewar手术方法的力学基础

The Dynamic Investigation of Modified Dewar's Operation

作者介绍了在Ｄｅｗａｒ手术原方法基础上，附加锁骨外侧端切除０．５～１ｃｍ的改良型手术方法及其原理。经１８例肩锁关节完全脱位治疗观察，从临床疗效、Ｘ线摄片和喙－锁间距（ｃ－ｃｄｉｓｔａｎｃｅ）以及三角肌与冈上肌肌电图检查等三方面结果，证实改良型Ｄｅｗａｒ手术可以预防术后肩峰与锁骨端的摩擦和撞击，避免肩锁关节骨性关节炎的发生。平均４年７个月随诊，临床疗效显示，１２例为优，６例为良，肌电图检查发现手术侧三角肌、冈上肌的运动单位电位和峰值电压与健侧对比无差异。上述结果说明，改良型Ｄｅｗａｒ手术符合生物力学原理，具有静力学与动力学双重复位作用，安全、有效。

?8 cases of complete dislocation of A-Cjoint included 6 old and 12 fresh patients were operated upon with the modified Dewar's operation from June 1983 to April 1996. There were 11 males and 7 females with average age of 34.5 years. X-ray examination showed complete separation of A-C joint and enlargement of the interval between the coracoid process and tuberosity of the clavicles.The modified Dewar's operation was based on the typical Dewar's method combined with an additional 0.5 cm resection of the distal part of the clavicle. This investigation included the clinical examination, roengenographic measurement of the distance of coracoid and the tuberosity of clavicle(C-CD), alignment of A-C Joint at elevation and hanging position, and E. M. G examination of deltoid and supraspinatus muscles. 12 cases had excellent and 6 had good results at mean 4 years and 7 months followed up study. The connection between A-C Joint were improved during the arm elevation or at the hanging position. Under the arm loading the A-C joints even got the over reduction with a minor inferior migration of the distalpart of clavicles.The E. M. G investigation showed no significant difference in supraspinatus and deltoid muscles on both sides. Dewar's procedure not only re-established the static stabilization but also regained the dynamic stability of the A-C connection.